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C23H25NO5, monoclinic, Cc(no. 9), a= 21.2548(2) Å, b= 20.4713(1) Å, c= 16.7944(1) Å, β= 126.267(1)°, V= 5,891.79(10) Å3, Z= 12, Rgt(F) = 0.0240, wRref(F2) = 0.0649, T = 293 K.

Complete oxidation of propane has drawn great attention in the fields of automotive emission control and volatile organic compound elimination. However, it is challenging to achieve high activity of this reaction due to the stability of propane. We here utilize a facile solvothermal method to construct tri-coordinated Al (AlIII) sites on the as-synthesized ST-Al2O3support to alter the properties of supported Pt species. It is demonstrated that AlIIIsites facilitate the dispersion and electron enrichment of supported Pt sites. Thus, Pt/ST-Al2O3exhibits a superior activity toward complete propane oxidation, showing a 6.7-fold improvement in the turnover frequency over commercial Pt/Al2O3catalysts. Meanwhile, Pt/ST-Al2O3possesses a distinct reaction route originating from its stronger C–H and C–C cleavage capability, while having excellent activity not only in complete propane oxidation but also in the complete oxidation of other alkanes (CH4, C2H6, and n-C4H10). In addition, the AlIIIconstruction strategy is successfully extended to more cases, e.g., Pd/ST-Al2O3with higher Pd dispersion and electron density. This work provides a promising strategy for the control of the oxide support for advanced design and synthesis of alkane oxidation catalysts.

C23H25FN2O, triclinic, P1‾$P\overline{1}$ (no. 2), a= 6.5011(2) Å, b= 11.2794(4) Å, c= 14.0796(6) Å, α= 110.246(4)°, β= 97.236(3)°, γ= 98.335(2)°, V= 941.01(6) Å3, Z= 2, Rgt(F) = 0.0476, wRref(F2) = 0.1366, T = 293 K.

AbstractWhereas students in China can take Chinese instrument training in a variety of settings, Canada has no systematized structure of Chinese music education. Indeed, little scholarly attention has been paid to the development of Chinese instrumental music education in the Chinese diaspora within North America. Based on extensive fieldwork in Toronto, I address the following questions in this article: How do Chinese immigrants pass down their music? How and where do students take Chinese instrument training? How have the methods of transmission evolved? And how do Chinese instrument pedagogical techniques bridge Chinese and Canadian contexts?

Dear Editor, This letter addresses the synchronization problem of a class of delayed stochastic complex dynamical networks consisting of multiple drive and response nodes. The aim is to achieve mean square exponential synchronization for the drive-response nodes despite the simultaneous presence of time delays and stochastic noises in node dynamics. Toward this aim, a hybrid impulsive controller, featuring both delayed and non-delayed impulses, is developed. Sufficient conditions of mean square exponential stability of the delayed stochastic synchronization error system are then derived. It is further shown that exponential synchronization can still be preserved even if the impulsive controller involves only delayed impulses. An illustrative example is finally presented to demonstrate the effectiveness of the obtained theoretical results.

Proteasomes are overexpressed in multiple myeloma (MM) and proteasomal inhibitors (PIs) have been widely used for the treatment of MM. PIs are reported to induce MM cell apoptosis but impair necroptosis. In the present study, we found that PIs MG132 and bortezomib induce MM cell pyroptosis, a novel type of cell death, in a GSDME-dependent manner. Lack of GSDME totally blocks PI-induced pyroptosis. Interestingly, we found that Caspase-3/6/7/9 are all involved in pyroptosis triggered by PIs because the specific inhibitor of each caspase ablates GSDME activation. PIs markedly reduce mitochondrial membrane potential. Moreover, PIs disrupt the interaction of Bcl-2 and BAX, induce cytochrome crelease from mitochondria to cytosol and activate GSDME. Furthermore, we found that overexpression of an N-terminal portion of GSDME suffices to release cytochrome cfrom mitochondria and to activate Caspase-3/9, suggesting N-GSDME might penetrate the mitochondrial membrane. Consistent with Bcl-2 inhibition, BAX can induce MM cell pyroptosis in a GSDME-dependent manner. In accordance with these findings, inhibition of Bcl-2 synergizes with PIs to induce MM cell pyroptosis. Therefore, the present study indicates that PIs trigger MM cell pyroptosis via the mitochondrial BAX/GSDME pathway and provides a rationale for combined treatment of MM with Bcl-2 and proteasome inhibitors to increase therapeutic efficiency via induction of pyroptosis.

Catalytic oxidation is the most effective method to eliminate in-door formaldehyde, and Mn-based catalysts with low cost and high activity have drawn great attention for this reaction. Herein, p-type semiconductor NiO doped MnOxcatalysts were prepared by an environmentally friendly oxalate co-precipitation method. The doped Ni species entered the lattice of MnOxto form amorphous Ni–Mn composite oxide/NiO and increased the ratio of surface Mn4+and total amount of surface active oxygen simultaneously with the increase of NiO content in the form of a volcano curve, which directly correlated to the abilities for adsorption and oxidation of formaldehyde. Among them, 0.2NiO–MnOx(Ni/(Ni + Mn) = 0.2) showed the highest activity, 300 ppm of formaldehyde can be completely eliminated at 98 °C in a 2.5 vol% H2O-containing atmosphere, and the corresponding specific reaction rate was about 2.9 times higher than that of pure MnOx. Meanwhile, the enhanced migration of oxygen species over NiO–MnOxcatalysts also promoted the replenishment of surface active oxygen that was consumed in the reaction process, which kept the activity of 0.2NiO–MnOxstable during the continuous reaction cycles and 26 h long-term stability test. Our study showed that utilizing NiO to regulate the reactivity and amount of surface oxygen species was an efficient way to improve the intrinsic catalytic performance of MnOx.

Monomer diffusion models are important in describing the formation mechanism of the volume holographic grating in photopolymers. The most representative of these models is the first-order diffusion model, which neglects the influence of the exposure intensity threshold and dissolved oxygen in a polymer. This model causes a significant deviation between the theoretical simulation and the experimental results. Therefore, we propose a modified monomer diffusion model, which is more consistent with experimental results on refractive index modulation than other models.

Chiral atomically precise metal clusters, known for their remarkable chiroptical properties, hold great potential for applications in chirality recognition. However, advancements in this field have been constrained by the limited exploration of host–guest chemistry, involving metal clusters. This study reports the synthesis of a chiral Cu16(C2B10H10S2)8(denoted as Cu16@CB8, where C2B10H12S2H2= 9,12-(HS)2-1,2-closo-carborane) cluster by an achiral carboranylthiolate ligand. The chiral R-/S-Cu16@CB8cluster features chiral cavities reminiscent of cyclodextrins, which are surrounded by carborane clusters, yet they crystallize in a racemate. These cyclodextrin-like cavities demonstrated the specific recognition of amino acids, as indicated by the responsive output of circular dichroism and circularly polarized luminescence signals of Cu16moieties of the Cu16@CB8cluster. Notably, a quantitative chiroptical analysis of amino acids in a short time and a concomitant deracemization of Cu16@CB8were achieved. Density functional tight-binding molecular dynamics simulation and noncovalent interaction analysis further unraveled the great importance of the cavities and binding sites for chiral recognition. Dipeptide, tripeptide, and polypeptide containing the corresponding amino acids (Cys, Arg, or His residues) display the same chiral recognition, showing the generality of this approach. The functional synergy of dual clusters, comprising carborane and metal clusters, is for the first time demonstrated in the Cu16@CB8cluster, resulting in the valuable quantification of the enantiomeric excess (ee) value of amino acids. This work opens a new avenue for chirality sensors based on chiral metal clusters with unique chiroptical properties and inspires the development of carborane clusters in host–guest chemistry.

Experimental study was conducted to investigate the seismic behavior of roof joint. Eight full-scale specimens were tested considering the effects of axial force, joint height, hole shape of base plate and edge distance of concrete on the failure mode and resistance capacity of roof joint. With the increase of axial force, the hysteretic curves were fuller. The mechanical model of roof joint change from bending to shear. With the increase of joint height, the ultimate strength of roof joint decreased. If the hole shape of base plate changed from circle to loose, the slip behavior of roof joint appeared and the ultimate strength of roof joint decreased. The damage of edge concrete may occur if the edge distance of concrete was not big enough.

The dual active bridge (DAB) converters are widely used in the energy storage equipment and the distributed power systems. However, the existence of switching nonlinearity and control delay can cause serious stability problem to the DAB converters. Thus, this paper, studies the stability of a digitally controlled DAB converter with an output voltage closed loop controller. Firstly, to accurately study the stability in a DAB converter, a discrete-time model established in a whole switching period is obtained. The model considers the output capacitor ESR, the digital control delay, and sample-and-hold process. By using this model, the stabilities of the DAB converter versus the proportional controller parameter and the output capacitor ESR are analyzed and the critical values are predicted accurately. Moreover, the stability boundary of the proportional controller parameter and the output capacitor ESR is also obtained. The result shows that the value of the output capacitor ESR can have a great effect on the stability region of the proportional controller parameter. Finally, the theoretical analyses are verified by the simulation and experimental results.

In concentrically braced frames (CBF), gusset plates as the connected members are subjected to forces not only from brace but also from frame action. When the braced frame is deformed, the beam-column connection will deform, and the deformation of beam-column connection either “open” or “close” as the brace under “compression” or “tension”. Therefore, the design of gusset plate should consider the effect of such frame action, in addition of the brace axial load. Six finite element models were developed using ABAQUS to investigate the force distribution of gusset plate under the two actions. It is noted that force in gusset plate can be divided into two parts and frame action is so small that can be neglected during brace buckling.

A promising trend in plasmonics involves shrinking the size of plasmon-supporting structures down to a few nanometers, thus enabling control over light–matter interaction at extreme-subwavelength scales. In this limit, quantum mechanical effects, such as nonlocal screening and size quantization, strongly affect the plasmonic response, rendering it substantially different from classical predictions. For very small clusters and molecules, collective plasmonic modes are hard to distinguish from other excitations such as single-electron transitions. Using rigorous quantum mechanical computational techniques for a wide variety of physical systems, we describe how an optical resonance of a nanostructure can be classified as either plasmonic or nonplasmonic. More precisely, we define a universal metric for such classification, the generalized plasmonicity index (GPI), which can be straightforwardly implemented in any computational electronic-structure method or classical electromagnetic approach to discriminate plasmons from single-particle excitations and photonic modes. Using the GPI, we investigate the plasmonicity of optical resonances in a wide range of systems including: the emergence of plasmonic behavior in small jellium spheres as the size and the number of electrons increase; atomic-scale metallic clusters as a function of the number of atoms; and nanostructured graphene as a function of size and doping down to the molecular plasmons in polycyclic aromatic hydrocarbons. Our study provides a rigorous foundation for the further development of ultrasmall nanostructures based on molecular plasmonics.

Polycyclic aromatic hydrocarbon (PAH) molecules, the hydrogen-terminated, sub-nanometer-scale version of graphene, support plasmon resonances with the addition or removal of a single electron. Typically colorless when neutral, they are transformed into vivid optical absorbers in either their positively or negatively charged states. Here, we demonstrate a low-voltage, multistate electrochromic device based on PAH plasmon resonances that can be reversibly switched between nearly colorless (0 V), olive (+4 V), and royal blue (−3.5 V). The device exhibits highly efficient color change compared to electrochromic polymers and metal oxides, lower power consumption than liquid crystals, and is shown to reversibly switch for at least 100 cycles. We also demonstrate the additive property of molecular plasmon resonances in a single-layer device to display a reversible, transmissive-to-black device. This work illuminates the potential of PAH molecular plasmonics for the development of color displays and large-area color-changing applications due to their processability and ultralow power consumption.

As a novel coupling beam for coupled shear wall structures, the bending-type frictional steel truss coupling beam (BFTCB) concentrates the deformation and energy dissipation in friction dampers at the bottom chord, allowing the main body to remain elastic during earthquakes. As the preparatory work for resilient structure design based on the BFTCB, this work concentrates on developing the hysteretic model for BFTCB. Firstly, the BFTCB stiffness-strength decoupling mechanism was introduced, i.e., the shear strength is provided by friction dampers while webs control its initial stiffness. Secondly, a hysteretic model that reflects the BFTCB two-stage sliding characteristic was proposed. The model consists of a trilinear backbone curve and the unloading and reverse loading rules. The model has eight control parameters, of which two core parameters (initial stiffness and limiting shear strength) are derived from the BFTCB stiffness-strength decoupling mechanism, whereas the remaining parameters are obtained by theoretical analysis and empirical calibration. The hysteretic model was then compared with the test curves and demonstrated good accuracy. Finally, a series of FE prototypes of BFTCB with different design stiffnesses and strengths was adopted to verify the hysteretic model. The results showed that the proposed model fitted well with the FE prototypes, indicating its applicability to BFTCB with varying core design parameters. Therefore, the hysteretic model can be adopted for BFTCB to support the resilient shear wall structure design.

Objective: The aim of this study was to explore changes in tumor tissues of glioma-bearing rats that underwent argon–helium cryoablation as well as changes in antitumor immunity before and after combined interleukin 12 treatment.Methods: Two hundred sixty Wistar rats were randomly divided into a blank control group, intravenous injection interleukin-12 group, cryotherapy group, and cryotherapy + intravenous injection group. C6 glioma cells proliferated in vitrowere implanted subcutaneously on the backs of rats to establish C6 glioma-bearing animal models. Each group underwent the corresponding treatments, and morphological changes in tumor tissues were examined using hematoxylin–eosin staining. CD11c staining was examined using immunohistochemistry, and differences in dendritic cells and T-cell subsets before and after treatment were analyzed using flow cytometry.Results: The control group showed no statistical changes in terms of tumor tissue morphology and cellular immunity, cryotherapy group, and cryotherapy + intravenous injection group, among which the count for the cryotherapy + intravenous injection group was significantly higher than those of all other groups. In the argon-helium cryotherapy group, tumor cells were damaged and dendritic cell markers were positive. The number of CD11c+ and CD86+ cells increased significantly after the operation as did the cytokine interferon-? level (P< .01), suggesting a shift toward Th1-type immunity.Conclusion: Combined treatment of argon–helium cryoablation and interleukin 12 for gliomas not only effectively injured tumor tissues but also boosted immune function and increased antitumor ability. Therefore, this approach is a promising treatment measure for brain gliomas.

High aspect ratios trench are commonly used in shallow trench isolation (STI) or Gate Poly-silicon structures by dry etching of a silicon substrate. During the dry etching process, polymerization residues are produced inside the trench. These polymerization residues must be removed before the next deposition process. Watermarks might also form by poor drying after the wet cleaning process of high aspect ratio structures, which can seriously affect the next process. In this paper, we show the performance of single wafer RCA cleaning technology in high aspect ratio structures. Polymer residues can be removed by diluted HF and SC1 with megasonic technology, without the appearance of watermarks after drying. This study focuses on polymerization residues and watermarks using inline defect detection to qualify the performance of single wafer RCA clean. Yield is the final verification for proving the single wafer RCA clean.

This paper presents an algorithm for two-stage homogenous strip patterns for rectangular pieces. The algorithm is appropriate for the shearing and punching process. It proposes the two-stage homogenous strip patterns that can be cut into homogenous strips in two stages, with another two stages being required to cut the strips into pieces. Firstly vertical cuts divide the stock sheet into segments, and then horizontal cuts divide the segments into homogenous strips. A homogenous strip contains pieces of the same type. The algorithm uses a dynamic programming recursion to determine the strip layout on each segment, solves knapsack problems to obtain the segment layout on the sheet. The algorithm is tested through benchmark problems, and compares with two famous algorithms. The pattern value and the computation speed of this paper’s algorithm are better than that of the classic two-stage algorithm. What’s more, this paper’s algorithm can give solutions very close to optimality.

Frequency Selective Surfaces(FSS) are periodic array structure, generally, FSS are designed on plane structure. In this article, design of FSS for curved radome will be developed. the parameter of FSS, which have some frequency response, will be given through simulation and optimization, and FSS plane model will be manufactured. The parameter will be modified, based on the configuration of streamline radome , the arrangement of FSS will be designed on curved radome, finally, the FSS Radome will be manufactured. it is shown that FSS under this method is satisfied.

Abstract: Objective: To investigate the antiproliferative and apoptogenic activities of peptide extracted from the Chinese toad (Bufo bufo gargarizans) skin (TSP) and its effects on hepatocarcinoma cell line. Methods: MTT assaywas used to detect the effects of TSP (50 μg/mL and 5 μg/mL) on the proliferation and viability of Hepatocarcinoma cell line (HepG2) and liver cell line (L-02); Flow cytometry was used in DNA content analysis to determine the cell distribution in different phases of cell cycle; Annexin V-FITC/PI stained fluorescence-activated cell sorter (FACS) and transmission electron microscope (TEM) were used to detect the apoptosis of the treated cells. Results: TSP could not suppress the proliferation and viability of normal liver L-02 cells, but strongly inhibited the proliferation and viability of HepG2 cells; TSP (50 μg/mL) primarily arrested the HepG2 cells at G1 phase of the cell cycle; TSP (50 μg/mL) induced apoptosis in HepG2 cells and enhanced the effects of 5-Fu. Conclusion: TSP has potent antineoplastic activity against human hepatocarcinoma cells with little toxicity to normal liver cells and can enhance the effects of 5-Fu.

Density functional theory computations were performed to investigatethe surface and edge effects on the structural and electronic properties of wurtzite GaN nanoribbons. For 2D GaN sheets terminated with (0001) direction, the surface effect is dominant and leads to a semiconductor-to-metal transition in both bare and surface hydrogenated GaN sheets. To investigate the edge effects, we constructed the 2D infinitely thick GaN nanoribbons with fixed (0001) crystal orientation to exclude the surface states, and such ribbons are always nonmagnetic semiconductors for both bare and hydrogenated systems, regardless of the edge shapes (armchair or zigzag). Two representative models for 1D GaN nanoribbons with finite width and thickness, namely, 7-bilayer 13-armchair and 9-zigzag GaN nanoribbons, were studied, which exhibit versatile electronic properties and variable band structures. These tunable properties could be extrapolated to wider (thicker) ribbons. Therefore, the surface effect, edge effect, and quantum size effect are three important factors that significantly alter the electronic properties of GaN ribbon systems.

The present study was designed to assess whether changes in glycolipids and cyclic AMP contents might serve as markers for the diagnosis of malignancy in the liver. The experimental model was a transplantable murine hepatoma. Experimental mice were divided into three groups: (1) a therapeutic group, which had been transplanted with hepatoma and treated with the antimetabolism drug 5-flurouracil (0.2 mg/day i.p.), (2) a control group, which had been transplanted with hepatoma and treated with 0.2 ml 0.9% NaCl/day and (3) a normal group of mice. The ganglioside and cAMP contents in the hepatoma tissue, plasma cAMP, total- and lipid-bound sialic acid levels and red blood cell membrane sialic acid levels were determined. Results showed that the ganglioside content, total and lipid-bound sialic acid levels in the control group were significantly higher than those in the livers of normal mice (p < 0.01) while these respective values in the therapeutic group were significantly lower than those in the control group (p < 0.01). The cAMP levels of tumor tissues and plasma in the control group were lower than those in normal mice. No significant difference in red blood cell membrane sialic acid content was observed between the therapeutic and control groups though levels for both were higher than those in normal mice. These results indicate that ganglioside content and sialic acid levels in hepatoma tissues were significantly elevated, and cAMP levels in hepatoma tissues were significantly decreased during proliferation and abnormal differentiation.

We investigated the effect of photoperiod on eggshell quality, bone quality characteristics and bone metabolism related enzymes and factors in laying ducks. After adaption, 300 Jinding laying ducks (252-day-old) were randomly divided into 5 treatments, receiving 12L(hours of light):12D(hours of darkness), 14L:10D, 16L:8D, 18L:6D or 20L:4D, respectively. Each group had 6 replicates of 10 birds each. The feeding experiment lasted 8 wk. Compared with 12L:12D, the higher values of eggshell breaking strength occurred in ≥18 h photoperiods at the end of 6 wk, and in ≥16 h photoperiods at the end of 4 wk, with the common highest values in 18 h photoperiod (P˂ 0.05). Besides, 18L:6D had higher values of ultimate load Fu and cortical cross-sectional area A in tibia, femur, and ulna (P˂ 0.05), compared with 12L:12D. The higher values of proximal bone mineral content (BMC; tibia), distal BMC (ulna), total Ca (tibia), and cortical volumetric bone mineral density (vBMC; tibia and ulna) were observed in 16L:8D and 18L:6D treatments (P˂ 0.05). Meanwhile, 18 h photoperiod group had the higher proximal BMC (femur) and total Ca in ulna (P˂ 0.05). In serum, compared with 12L:12D group, the higher ALP activity occurred in ≥16 h photoperiods (0:00 and 18:00), with the highest values in 18L:6D treatment (P˂ 0.05); the higher values of TGF-β (6:00) and OC (6:00 and 18:00) were simultaneously observed in 18 h photoperiod (P˂ 0.05). Moreover, values of trACP activity, TNF-α and IL-6 contents decreased in ≥18 h photoperiods at 0:00 (P˂ 0.05), compared with 12L:12D group. To sum up, an appropriate photoperiod could improve eggshell quality, bone strength and mineral content through increasing osteogenesis during the light time and decreasing resorption activity during the dark, and 18 h is an adequate photoperiod for the eggshell and bone quality of laying ducks.

In this paper the author uses the principle of Maxwell's equal area to study the liquid-vapour phase transition and to discuss the stability of the phase transition.The results obtained are quite analogous in behaviour to those of the Van der Waals' type.

Catalytic oxidation is believed to be the most efficient method for indoor formaldehyde purification. Herein, we reported that the Pt/Na-ZSM-5 catalyst with low Pt loading (0.16 wt %) prepared by depositing Pt on Na+ion-exchanged ZSM-5 could completely oxidize 300 ppm formaldehyde in 2.5 vol % H2O at 32 °C and maintain its activity during the 62 h-long stability test. Multiple characterizations revealed that the presence of Na species significantly enhanced formaldehyde adsorption ability and made Pt species tend to exist in the form of metal Pt through electron transfer from Na to Pt, which promoted the activation of oxygen and opened a new efficient formaldehyde oxidation pathway, namely, direct decomposition of formate. The synergistic effects resulted in the TOF of Pt(0.16)/Na-ZSM-5 being about nine times higher than that of Pt(0.50)/ZSM-5. Our study showed that utilizing an alkali metal to tune the surface acidity/basicity of the support and the state of the supported noble metal was a promising way to improve the intrinsic catalytic performance and reduce noble metal usage.

We investigated the effect of photoperiod on performance, ovarian morphology, reproductive hormones levels and their receptors mRNA expressions in laying ducks. After adaption, 300 252-d-old Jinding laying ducks were randomly allocated to 5 groups, receiving 12L(hours of light):12D(hours of darkness), 14L:10D, 16L:8D, 18L:6D or 20L:4D, respectively. Each treatment had 6 replicates of 10 birds each. The feeding trial lasted 8 wks. Egg production, egg mass and average daily feed intake increased linearly and quadratically with increasing photoperiods (P˂ 0.05), and the higher values of them occurred in photoperiods ≥ 16 h, compared with 12L:12D (P˃ 0.05). Initial and bare stroma weight increased quadratically, while total large white follicles (LWFs) number and weight increased linearly and quadratically, with increasing photoperiods (P˂ 0.05). The higher values of them occurred in 16L:8D and 18L:6D treatments as well as the higher total LWFs weight also occurred in 20L:4D, compared with 12L:12D (P˃ 0.05). Besides, 16.93 and 16.93 h were the optimal photoperiods for bare stroma (follicles ≥ 2 mm in diameter removed) weight and total LWFs weight respectively, calculated from reliable regression equations (R2≥ 0.5071). Compared with 12L:12D, the higher levels of estradiol, progesterone, follicle-stimulating hormone (FSH) as well as the higher expressions of estrogen, luteinizing hormone (LH) and progesterone receptors were observed in ≥ 16 h photoperiods (P˂ 0.05), while the higher LH level and FSH receptor expression only occurred in 16L:8D and 18L:6D (P˂ 0.05). In the hypothalamus, higher mRNA expression of gonadotropin-releasing hormone occurred in 16L:8D and 18L:6D groups (P˂ 0.05). Meanwhile, gonadotropin-inhibitory hormone and prolactin increased in 20-h photoperiod (P˂ 0.05), and the latter may be due to the up-regulation of vasoactive intestinal peptide expression (P˂ 0.05). To sum up, an appropriate photoperiod could improve the performance, reproductive organs and ovarian follicles development through reproductive hormones and their receptors, and 16.56-10.93 h is an adequate photoperiod for laying ducks.